How I automate cold email with agents

Most people think cold email infrastructure takes a full team.

You find the leads. Verify the emails. Warm up accounts. Write sequences. Distribute campaigns. Check reply rates. Optimize sequences.

We are talking about a three, four person operation. Maybe three weeks to get it done.

Not anymore.

We set up our entire cold email operation this week with agents running inside OpenClaw and our Single Brain system. What took our team weeks now takes an afternoon. And by afternoon I mean literally about an hour of my time.

Here is exactly how it works.

Agents read your campaigns in real time

First, I ask the agent: tell me about the Instantly campaigns this week. What is performing versus what is not?

The agent hooks into the Instantly API through OpenClaw. It looks at the campaigns that are working and the ones that are not. It pulls historical reply rates. It knows which ones we paused. It knows which ones are generating 2 to 4 percent reply rates versus the ones tanking at 0.5 percent.

You ask follow up questions. The agent answers from live data. No manual dashboards. No copy paste.

Agents rewrite winning sequences automatically

Here is where this gets interesting. When the agent finds a sequence that is hitting 16 percent positive reply rate, it doesn’t just flag it. It uses it.

I feed it historical Google Drive documents with our winning sequences. The agent reformatting them in real time. It applies the patterns that are working now to whatever new campaign we are launching.

I reviewed one that had been running and told the agent the two new campaigns it created did not feel right. In the past this would take two hours of review. I told it to go faster. It spit back a Google Doc in seconds.

Then it scored every sequence recursively on a scale of 0 to 100 until it reached 90 plus. Only then does it return anything to me for review.

Still a little subjective because you need a human with taste at the end. But at least the agent is using data from your actual past winners as the baseline.

Custom variables are the hidden killer

This is something I caught while reviewing the output and almost never think about.

If your custom variable says Eric is your first name but the first name was not entered in the lead list the email falls back to “there”. If you get an email that says “there”, you immediately know it’s automated and you delete it.

The agent checks this. It catches it. It fixes it. I barely had to touch anything.

Multiple sequences, one brain

I had the agent work on the Single Grain cold email sequences and a customer campaign simultaneously. Different rules for each. Different incentives. Different lead lists.

It was just me dictating outcomes and the agents executing. Not a single manual step in the loop.

In maybe 10 minutes I had a fully optimized, multi campaign cold email operation loaded in Instantly. The agent handled lead redistribution, send limits, inbox duplication checks, everything.

What used to be a team job is now a one person operation. You are literally a one man wrecking crew when you have this setup.

Why this matters

Cold email is not going anywhere. It is one of the highest ROI channels available. But the infrastructure to run it well used to be a full department.

Now it is an agent workflow. The bottleneck is not finding people. It is having taste to review the output.

If your buyers are asking ChatGPT and Claude for vendor recommendations before they ever contact you, you need a cold email infrastructure that can stand up fast, iterate fast, and run itself.

The tools are ready. The agents handle what used to be a team. Your job is to review and decide.

That is the new cold email operation.

Watch the full breakdown here: https://www.youtube.com/watch?v=rgSNYrJY9YY

To building smarter,
Eric Siu

P.S.

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